Various means have been provided for supplying an electrode connection to a battery terminal. Where a fiber structure electrode framework of metallized plastic fibers is provided, it has been taught, as in U.S. Pat. No. 4,755,441, to weld a current-conducting lug to a reinforced edge of the electrode framework. The current-conducting lug is provided with a stepped area to which the welded connection is made.
U.S. Pat. No. 5,558,681 discloses a method of bonding a metal connection to an electrode having a foam support structure, including a main core and a retaining core. A metal strip is affixed to the support by welding under compression. The strip may be welded along the edge of a retaining core which has been previously disposed to the main core, or the strip can be positioned between the main core and the retaining core.
A connection tab may be made from a single piece of metal foam, as is taught in U.S. Pat. No. 5,578,397 which describes a method of forming an electrode plate and plate head which includes a connection tab. Such connection tab is formed by compressing the support in two directions, resulting in a connection tab having a density of 2.5 times the density of the metal foam support.
It has also been taught to install a connection tab by removing sections of active material where such tabs are to be located and then attaching a thin strip of material such as by spot welding. Thus, U.S. Pat. No. 5,549,717 describes an electrode provided with an electrical lead or tab which has been welded on the outer surface of the electrode in such a manner that the outer surface of the tab is substantially flush with the outer surface of the electrode.
It would, nevertheless, be desirable to provide a foam substrate connection zone which could provide an integral bus to which a connection tab could be secured. It would also be advantageous to provide increased electrical conductivity of an electrode formed from the foam substrate with such connection tab.